ABSORPTION VS DIFFUSION
There are basically 3 types of sound treatments: absorption, diffusion and barrier. Sound barriers are fairly self explanatory so we will focus on the other two.
Absorption removes or absorbs sonic energy by converting it to heat. "So that's why my studio gets sooo hot!" Not exactly... but I digress:)
Fiberglass, rock wool, and foam are common types of absorption materials often set in a wood frame and covered in felt or some other acoustically transparent material.
A diffusor disperses acoustic energy. This is useful when you don't wish to remove acoustic energy from your space, you just want it less defined.
These tools do interact with each other. For example, diffused sound is easier to absorb. Picture using a spray bottle on a large sponge. Set the bottle to stream and the water will quickly saturate a small spot on the sponge and begin to reflect and run off. Set the bottle to spray and much more water will be absorbed.
We will go into more detail in the future, but those are the basics.